Comparison of the plantar pressure distribution and mechanical alignment in patients with varus knee osteoarthritis following high tibial osteotomy.

PURPOSE: The changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment. METHODS: Between May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated. RESULTS: The WBL%, HKA and TPI angle changed significantly after HTO (P < 0.001). The preoperative group exhibited a lower peak pressure in the HM region (P < 0.05) and higher peak pressure in the M5 region (P < 0.05); the pre- and postoperative groups exhibited a lower peak pressure in the HC region (P < 0.05); the rearfoot MLPR was significantly lower and LS-COP was significantly higher in the preoperative group (P = 0.017 in MLPR and 0.031 in LS-COP, respectively). Comparison among the SV, MV and LV groups, the SV group indicated a lower peak pressure in the HM region (P = 0.036), and a lower MLPR in the rearfoot (P = 0.033). The KOOS Sport/Re score in the MV and LV groups increased significantly compared with the SV group (P = 0.042). CONCLUSION: Plantar pressure distribution during the stance phase in patients with varus knee OA following HTO exhibited a more medialized rearfoot plantar pressure distribution pattern than that before surgery. Compared with the small valgus alignment, a moderate to large valgus alignment allows patients to walk with a more even medial and lateral plantar pressure distribution, which is more similar to healthy adults.

External fixation in early treatment of unstable pelvic fractures.

BACKGROUND: Patients with pelvic fractures are often treated in hospitals without the capacity to implement an open reduction internal fixation (ORIF). This often leads to pelvic malunion in patients with unstable pelvic fracture, shock or even death due to uncontrollable pelvic hemorrhage and unstable hemodynamics. This study explored the role of early external fixation (within 7 days) for patients with unstable pelvic fractures. METHODS: A retrospective analysis was conducted on 32 patients with unstable pelvic fractures treated with early external fixation from January 2005 to January 2010 (Tile type B: 18 cases; C: 14 cases). The study comprised 28 males and 4 females, with a mean age of (32 ± 8) years (range, 21-56 years). Of these patients, 22 were treated with emergency pelvic external fixation and 10 were treated with external fixation within 1-7 days. Fifteen cases suffered traumatic hemorrhagic shock. A statistical analysis was conducted to compare fluid infusion and blood transfusion volumes within the first 24 hours of these shock patients with another cohort of patients treated without early external fixation from January 1993 to January 1998. RESULTS: The average follow-up was (34.7 ± 14.6) months (range, 6-66 months). Six to eight weeks after external fixation, patients could walk with crutches; by 12 weeks, external fixation was removed and all fractures had healed. Seven patients presented with sequelae, including 3 patients with long-term lumbosacral pain, 3 patients with erectile dysfunction and 1 patient with Morel-Lavallee lesion and other complications. The 15 shock patients in this study (2005-2010 group) required significantly lower volumes of fluid infusion and blood transfusion (P(fluid) = 0.000; P(transfusion) = 0.000) as compared to the 1993-1998 cohort. CONCLUSIONS: The early application of external fixation in unstable pelvic fracture patients positively affects hemodynamic stability, with outstanding efficacy as a final fixation option for unstable pelvic fractures.

[Screening and identification of mimic epitopes of monoclonal antibodies against hantaan virus using phage display technique].

AIM: To obtain mimic epitopes of monoclonal antibody (mAb) against Hantaan virus, and identify preliminarily their immunological characteristics. METHODS: Group-specific mAbs F3 and B11 were used as selective molecules for biopanning. After biopanning, the positive phages were identified by ELISA and DNA sequencing. Among the positive phages, F3-8, B11-18, B11-20 and B11-24 were selected to immunize BALB/c mice three times, respectively. The antiserum was then titered and confirmed by sandwich ELISA and competition ELISA. RESULTS: After 3 to 4 rounds of effective screening, the majority of the selected clones were found able to react to mAb F3 or B11 in a dose-dependent manner, but not to BSA, rHBsAg or other unrelated mAbs. The amino acid sequences of the clones binding to mAb F3 contained an identical sequence MHGPTKNQMWHT, which had higher homology to 750-759 amino acids between a pair of cysteines within glycoprotein G2 of HTNV/SEOV, while those of clones binding to mAb B11 had no evident homologous regions within HTNV/SEOV proteins. The specific antibodies increased significantly following immunization with phage peptides, which indicated that the phage-displayed peptides had not only good antigenicity, but also strong immunoreactivity. CONCLUSION: The phage-displayed peptides could mimic the epitope of HFRSV antigen, which would provide the potential for preparing more effective epitope-based vaccines and specific diagnostic reagents.